Spanner supports the ON DELETE SET NULL foreign key action for GoogleSQL and PostgreSQL dialects.

Spanner supports approximate aggregate functions for both GoogleSQL and PostgreSQL dialects.

These functions produce statistical estimates of distinct counts, allowing you to compute results faster and save resources on large datasets compared to exact aggregation.

Spanner supports automatic parameterization of SQL query literals to improve query performance, reduce latency, and lower CPU costs.

Spanner converts literal values hardcoded in CRUD-style queries, such as primary key lookups, index lookups, and primary key joins, into query parameters, allowing execution plans to be cached and reused to reduce latency and CPU costs.